FAQ 7.2: What are all these $@%&* punctuation signs, and how do I know when to use them?

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7.2: What are all these $@%&* punctuation signs, and how do I know when to use

    They are type specifiers, as detailed in perldata:

        $ for scalar values (number, string or reference)
        @ for arrays
        % for hashes (associative arrays)
        & for subroutines (aka functions, procedures, methods)
        * for all types of that symbol name.  In version 4 you used them like
          pointers, but in modern perls you can just use references.

    There are couple of other symbols that you're likely to encounter that
    aren't really type specifiers:

        <> are used for inputting a record from a filehandle.
        \  takes a reference to something.

    Note that <FILE> is *neither* the type specifier for files nor the name
    of the handle. It is the "<>" operator applied to the handle FILE. It
    reads one line (well, record--see "$/" in perlvar) from the handle FILE
    in scalar context, or *all* lines in list context. When performing open,
    close, or any other operation besides "<>" on files, or even when
    talking about the handle, do *not* use the brackets. These are correct:
    "eof(FH)", "seek(FH, 0, 2)" and "copying from STDIN to FILE".


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